Worm Towers

A worm tower with a PVC lid, installed close to a tree

“Create an instant home for worms in your garden, with a worm tower!”

A worm tower acts like a high rise hotel for worms, allowing them to enter, stay, eat and leave, always below ground away from predators. It creates a suitable home for composting worms (who don’t like to travel much), and for the various types of earthworms in your area. Worm towers can be used instead of worm farms or in conjunction with worm farms, and can be dug up and moved around the garden to help build up worm populations and soil fertility.

Benefits:

  • Improves soil
  • Encourages earthworms
  • Takes kitchen scraps
  • Easy to make

Materials:

  • Large PVC pipe
  • PVC lid
  • Cardboard box
  • Composting worms

Jump to:

How Does a Worm Tower Work?
How to Make a Worm Tower
How to Start a Worm Tower
Moving a Worm Tower
FAQ
How deep should my worm tower go?
What can I feed into my worm tower?
What else can I use for a lid?
Do I need to flush my worm tower?
Do I have to keep adding worms?
Related Articles
How to Worm Farm
Encouraging Earthworms
Worm Troughs
Worm Bags
Worm Stations

A worm tower with a PVC lid, installed close to a tree

A worm tower with a PVC lid, installed close to a tree

How Does a Worm Tower Work?

Composting worms stay in and around worm towers, eating decaying kitchen scraps, and distributing their castings in the soil as fertiliser for plants. Earthworms, who usually occupy deeper soil, enter toward the bottom of the tower through drill holes, also eat scraps, and spread castings throughout the garden. As the scraps are eaten, the content sinks down and more scraps can be added. The holes in the buried half of the tower allow enough air to percolate into the tower, so that a lid can be secured on top without causing problems. A lid is used to prevent moisture escaping, and animals from accessing the scraps. In dry seasons a worm tower serves as a refuge for worms, though it is recommended that the surrounding area be kept moist.

How to Make a Worm Tower

A worm tower with plenty of drill holes, ready for installing

A worm tower with plenty of drill holes, ready for installing

  • Cut a length of large PVC pipe about 1 meter long.
  • Measure halfway along its length, and decide which half will be buried, and which will stick up out of the ground.
  • Drill lots of holes (big enough for your pinky finger to poke through) in the half that is to be buried.
A worm tower positioned halfway in the ground, ready for backfill

A worm tower positioned halfway in the ground, ready for backfill

Dig a hole in your garden – somewhere near trees is best, deep enough to fit your worm tower halfway, so that all the drill holes are below ground level. Replace soil around the tower, securing it in place. It should be an empty pipe all the way down.

How to Start a Worm Tower

Your worms will need bedding to retreat to, and to venture from to find food. Shredded cardboard makes excellent worm bedding.

  • Shred cardboard into the bottom of the tower. Wet the cardboard.
  • Add composting worms. They will retreat into the bedding.
  • Add a layer of kitchen scraps.

Replace the lid of your worm tower, and check back in a few days to see if the contents have sunken.
Worms wait until scraps are breaking down before they start eating them, so it may take a week or so for them to really get into it. Don’t add any more scraps until you’ve seen the contents sinking, and add sparingly at first until they are happily eating everything you add.

Moving a Worm Tower

As your soil improves, and worms are populating the area around your worm tower, you can carefully dig up your tower and move it to another bed. Bed by bed you can build up soil fertility in your garden, and repeat again.

I recommend moving your worm tower to a shaded place near a tree. Under trees is the natural environment for most composting worms, and they will migrate their, allowing you to eventually move your tower (to the next tree!).

Frequently Asked Questions

How deep should my worm tower go?

While composting worms prefer to stay close to the surface, different earthworms occupy many depths in the soil. If you install your worm tower 50cm deep, your scraps will be catering to a wide range of worms, who in turn will fertilise your soil at different depths.

What can I feed into my worm tower?

Anything you can feed into a worm farm, you can feed into a worm tower; fruit and veggie scraps (excluding onion and garlic), egg shells (crushed), cardboard, newspaper, hair and fingernail clippings. It’s best to add a mix of things, and a little at a time, so that worms have a range of foods to choose from, and can distribute a good range of minerals in their castings around your garden. Large amounts of any one material will likely cause problems. If you have excess scraps or any other worm farm materials, consider composting them!

What else can I use for a lid?

A perfectly fitting lid is not necessary for your worm tower; the lid is only there to stop moisture getting out and birds and flying insects getting in.

  • An empty plant pot, turned upside down, does a great job as a lid. However, it may still let flies in, so consider fitting some old flyscreen over the outside, or packed in on the inside.
  • A brick or stone will do a fine job of protecting your worm tower. Choose one that can be easily removed and replaced.
  • A bowl for bird seed or water for birds can be used as a lid – duel purpose! Just make sure it’s easy to remove and replace.

Do I need to flush my worm tower?

No. Flushing will only wash nutrients out of the tower into the subsoil, where most plants can’t access them. If you open your worm tower and find it a bit dry, just add enough water (misting with a hose is enough) to moisten the environment. Worms will venture out of the tower, and deposit their castings throughout the surrounding soil. If ever the conditions are imbalanced in your worm tower, they will evacuate and return when the problem naturally resolves. Just stop feeding and wait for the contents to sink.

Do I have to keep adding worms?

No. Composting worms will adjust their population to suit the amount of food available. If you’re consistent with your feeding, they will maintain an adequate population for your needs.
However, if you are worm farming in a worm farm, you can keep adding your surplus worms to your worm tower. Just make sure you feed your tower adequately so there’s enough for all the worms to eat.

Related Articles

How to Worm Farm

“Let the worms do the work, with worm farming!”

Encouraging Earthworms

“Earthworms are a gardener’s best friend!”

Worm Troughs
Worm Bags
Worm Stations

 

12 comments on “Worm Towers

    • Hi Zen, thanks for your question! If you’re looking to encourage earthworms already in your veggie beds, I recommend Worm Stations, which are smaller than worm towers, but easy to make a lot of. If, however, you want to introduce worms to your beds, I suggest making one worm tower for each bed, or just make one and move it from bed to bed each season. I’ll have an article up on Worm Stations soon – stay tuned!

      • Thanks for the reply Shaun. What do you think of burying the scraps straight in the ground then? Sort of like chop and drop except they are veggie scraps.

        • Burying scraps is not a great practice – they quickly turn into a foul-smelling sludge full of acids. However, if you’re thinking of burying scraps, I recommend trying Bokashi. Just put your scraps into buckets, sprinkle in some bokashi bran, and seal the lid on the bucket. After a week or so you can bury the scraps and they’ll break down quickly and nicely in the soil – no problemo. I use bokashi to store my scraps for batch composting in a tumbler – works a charm!

  1. Hi shaun. We have added worm towers to a recently established raised garden bed. One of the towers has been taken over by large white larvae of some sort. Is this indicating a problem of some sort?

    • Hi Leeza, thanks for your question. There’s no need to worry about maggots or larvae in your compost, worm farms or worm towers. They are breaking down materials into fertiliser (humus), and sometimes even faster than worms! As for indication – I like your thinking! – maggots and larvae tend to show up when a compost pile, and in your case a worm tower is very wet (‘dampness’ is adequate, ‘wet’ risks an anaerobic environment). Check to see that you’re not over-watering your garden beds (mulch helps reduce water demand immensely!), and that some air can penetrate your worm towers. You could also use a stick to poke some holes down through the wet materials to allow air to get right down in there and help balance the situation. Let me know how things turn out!

  2. Thanks for the article Shaun and for the tips in the comments. I do need to start crushing my eggshells…

    Some friends used a 5-gallon bucket design that allowed a bit more capacity for the scraps.
    I adapted one for my kitchen garden (Was actually just being lazy and didn’t want to dig down for a 5-gallon bucket) to used 2-gallon containers. I’d love to hear your thoughts. http://bit.ly/UYDjbp

    Thanks,
    -Ryan

    • Hi Ryan,

      Materials for worm towers are endless. I imagine you could make a temporary one using only cardboard, all the way to using galvanised stainless steel. It’s a great opportunity to use materials you’ve already got on hand. Some people turn an empty plant pot upside down and cut the top off. These are specifically called ‘worm stations’, but function similarly to a worm tower. I don’t imagine different sized containers creating problems, only be sure not to feed in too much scraps, otherwise things could go anaerobic and smelly!

      If you want to try using a 5 gallon bucket, have a look in the bins at building sites – the painters and plasterers tend to go throw away a lot of good buckets.

      Good things

  3. I like the idea of a worm tower as they don’t take up much space. I have a 20 metre long fence line that we have planted block out trees. Could you use a worm tower a different points and if so how far apart would you place them?

    • Hi Kyla, thank you for your question. Composting worms will do well under your trees, because that is their natural habitat. You can use upside-down plant pots as ‘worm stations’ under each tree. Cut the bottoms off the pots and use them as lids, add kitchen scraps whenever you see the previous scraps disappearing. Regular earth worms won’t necessarily stay in one place, nor will they venture above ground in this way, so if you can’t get red tiger composting worms, encourage the local earthworms by burying scraps around the trees, or install worm towers (which go deeper underground) near the trees. I hope this helps. Let me know what you end up doing.

  4. I am keen to try this. A member of our community garden just posted your link. My question is: Do these attract rats? Would it hurt to make the tower longer and bury them deeper to deflect rats? Do the worms exit the tower through the holes or underneath. If the former, can you cap the lower end to make it rat proof? Thanks. This is such a cool idea!

    • Hi Ann, my tower has been in place for some years now and rats haven’t made any effort to get inside. If it were a problem though, you could wrap the whole thing in vermin-proof chicken wire. Capping the bottom wouldnt cause any problems i can think of, so long as excess water can escape through the holes.

      Good luck!

Leave a Reply

Your email address will not be published. Required fields are marked *

*

HTML tags are not allowed.